1. Field of the Invention
The present invention relates to an image forming apparatus that forms an image on a sheet.
2. Description of the Related Art
A transfer unit transfers an image to a sheet, and a fixing unit fixes the image on the sheet. The image transferred by the transfer unit remains unfixed until the image is fixed by the fixing unit. Hence, contact to an image surface side of the sheet needs to be avoided while the sheet is conveyed between the transfer unit and the fixing unit.
Thus, in order to convey the sheet without touching the image surface side of the sheet, a suction conveyance unit that suctions and conveys the sheet is provided between the transfer unit and the fixing unit (e.g., refer to Japanese Patent Laid-Open Nos. 2007-78997, 3-128851, and 11-65188).
There has recently been a rise in demand for a technology that enables formation of images on various types of sheets. In the case of conveying a sheet of high stiffness (large grammage), there may be following problems.
Depending on an inclination in the suction conveyance unit, the sheet plunges, not in accordance with the suction conveyance unit, into the fixing unit while maintaining an almost linear shape. When a leading edge of the sheet plunges into the fixing device, a part of the sheet is still in the transfer unit. Thus, the shock generated when the sheet plunges into the fixing unit is transmitted to the transfer unit via the sheet, causing a defective image.